Masai Mara’s Vanishing Animals

In April, I visited Kenya’s Masai Mara reserve and wrote about my concern that it was being loved to death. Now, unfortunately, a new study seems to back up my fear that wildlife in the park are faring badly–though according to the research, the culprit isn’t tourism but expansive livestock grazing in the larger Mara ecosystem.

Joseph O. Ogutu of the University of Hohenheim and colleagues from Kenya and South Africa analyzed aerial data that the Kenyan government collected from 1977 through 2009 in the Masai Mara reserve and the surrounding areas, which are home mainly to Maasai cattle-grazing communities. Overall, wildlife numbers plummeted by at least 70 percent during that period–with giraffes, zebras, warthogs, Thompson’s gazelles, impalas and more than a half dozen others all in decline.

Animals inside the park appeared to be no better off than those outside its boundaries (which aren’t fenced)–which calls into question a decade’s worth of beefed-up conservation efforts inside the reserve.

Most wildlife species have declined toward a third or less of their previous abundance within the overall Mara region between 1977 and 2009, with these decreases being almost as severe within the reserve as in the adjoining ranches. Hence, the earlier downward population trends of most wildlife species (Broten & Said, 1995; Ogutu, 2000; Ottichilo et al., 2000, 2001; Serneels & Lambin, 2001) have continued. Not only have resident populations decreased, but the numbers of migratory wildebeest and zebra entering the Mara region during the dry season have also shrunk, although no change in the source populations in the Serengeti ecosystems has been recorded (Sinclair et al., 2007). The biomass of livestock as a per cent of total livestock and wildlife biomass recorded within the reserve boundaries increased from an average of 2% in the 1970s to 23% in the 2000s and now greatly exceeds that of any resident wildlife species, except buffalo.

Ogutu told the BBC he was stunned by what he found, and that he’d expected to discover wildlife numbers in the park were on the rise. “But to our great surprise, the extreme wildlife declines have continued unabated in the Mara,” he said.

In the paper, the researchers finger “expanding human population” and “livestock influences” in the neighboring areas. But in the BBC interview, Ogutu was more specific, saying cattle numbers have tripled inside the reserve. He also said poaching is a constant problem.

When I visited the Mara, a Maasai warrior I met told me his friends often graze their animals inside the park boundaries. (He also revealed that they regularly hunt lions.)

In the Journal of Zoology paper, the scientists conclude that the future of the whole Mara region’s wildlife now rests on the success of conservation efforts outside the park–a worrisome state of affairs. This is increasingly true of protected areas around the world, including the U.S.: take, for instance, Yellowstone National Park, where the fate of the West’s iconic bison hinges on what happens to them when they roam across borders invisible to them. (I wrote about this last spring.) As difficult as it is to protect species and ecosystems on official conservation land (from, for instance, the off-road tourism I witnessed), it’s even harder to do so outside those arbitrary lines.

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